This invention relates to tape winding machines in general and more particularly to a novel type of splicing block for use in aligning the various pairs of tape to be spliced.
Machines used to transfer magnetic recording tape used in video or audio applications from the large supply reels prepared during manufacture and winding the tape on smaller reels or hubs, such as those commonly employed in tape cassettes and cartridges are well known in the art. See, for example, U.S. Pat. Nos. 4,061,286, 3,753,834, 3,637,153, 3,997,123, and 4,204,898. The typical procedure is to start with first and second hubs connected by a leader tape, sever the leader tape and splice virgin or prerecorded magnetic tape to the leader tape attached to the first hub, wind a given amount of magnetic tape onto that hub, splice the trailing end of the magnetic tape to the leader on the second hub and then mount the two hubs in a cassette housing. Alternatively, the winding procedure may be conducted while the hubs are already mounted in the cassette.
The splicing operation is automated through the use of a plurality of splicing blocks which may be moved relative to each other in order to bring selected tape ends into abutting relationship. As disclosed in U.S. Pat. No. 3,753,835 for example, a pair of moveable splicing blocks, each having a tape guideway, are alternately brought into juxtaposition with a fixed splicing block having a similar guideway. In an alternative arrangement, illustrated in U.S. Pat. No. 4,061,286, a single linearly reciprocating splicing block having two tape guideways--one for each of a pair of tapes--on reciprocating alternately aligns the guideways with a guideway on a fixed splicing block.
In loading cassettes with either device, an end of a supply of virgin or prerecorded tape is positioned on one of the moveable tape guideways, and held there (e.g., by a vacuum hold down or similar mechanism). The other moveable guideway is aligned with the fixed guideway, and the leader connected between the pair of hubs in the cassette is secured across the pair of aligned guideways (again, for instance, by a vacuum). A cut is made across the leader between the pair of aligned guideways, and, while the leader is still being held to the two guideways, the moveable guideways are shifted so as to align the end of the supply tape with the end of the leader at the fixed guideway. A splice may now be made between this piece of leader and the supply tape, the vacuum of the two now aligned guideways released, and the leader and the supply tape wound to the hub. After the desired amount of tape has been wound, the winding action is stopped, and the vacuum is again applied to the pair of aligned guideways so as to secure the supply tape. The supply tape is now severed between these two guideways and the moveable guideways are again shifted back to their original position, bringing the portion of leader affixed to the second hub into alignment with the trailing edge of the magnetic tape just supplied to the first. A splice is now made between the trailing edge of the supply tape and the leading edge of the leader. The vacuum hold down of the two aligned guideways is now released, and the winding operation is completed. A new leader may now be brought into alignment with the aligned pair of guideways and the operation repeated.
These prior art mechanisms, while satisfactory, are mechanically complex. Those designs in which two independent splicing blocks are alternately brought into alignment with a stationary block require, in addition to the plurality of mechanisms, precise synchronization and alignment. In those systems in which a single reciprocating splicing block contains a plurality of guideways, precise alignment of the ways supporting the movable block is required in order to insure proper operation and avoid unnecessary wear. Either of these prior art devices accordingly require care in assembly and maintenance. Additionally, the arrangement having two movable splicing blocks and a stationary splicing block is slower in operation than the one having a single reciprocating block.
Accordingly, it is an object of the present invention to provide a mechanism to align two or more tape paths to a stationary tape path which both has few moving parts and requires little or no adjustment or alignment, and which consequently is simple to manufacture and assemble. It is a further object of the present invention to provide such a mechanism which requires minimum maintenance and yet will suffer little bearing wear.